1. Field of the Invention
This invention relates to safe diacyl peroxide solution compositions capable of safe handling, transportation, use, and storage at ordinary atmospheric temperatures; also to safe methods of preparation of such solution compositions.
2. Description of the Prior Art
The short chain diacyl peroxides in this invention, namely those peroxides derived from carboxylic acids having 2-6 carbon atoms, are valuable polymerization initiators or catalysts. In the pure state these peroxides are extremely hazardous compounds; they are very sensitive to impact and shock; brisant explosions result if they are heated rapidly. For these reasons their commercial preparation and use has been limited.
However, some solution compositions are known. Diacetyl peroxide is available commercially only as a 25% solution in dimethyl phthalate; but dimethyl phthalate, a non-volatile plasticizer which is present in considerable quantity, limits the use of the solution to certain polymerization operations, in which the presence of this quantity of this plasticizer is not detrimental. Dipropionyl peroxide, was until recently marketed as a 25% solution in heptane. However, evaporation of the heptane concentrated the peroxide and resulted in a very shock sensitive residue. Diisobutyryl peroxide has not been commercially available because of its hazardous properties.